Electronic control unit having integrated circuit element and standalone test unit for integrated circuit element

Abstract

There is provided a low-cost electronic control unit that is capable of performing its hardware check every start and stop of the electronic control unit. A monitoring and control circuit section that is an integrated circuit element built in the electronic control unit includes a self-test circuit configured with a built-in self-test control block, scan chain circuits and mask circuitry, and performs a self-test using the built-in self-test control block and a partial combination of the scan chain circuits at start of the operation. In the shipment inspection of the integrated circuit element alone, an external test is performed by a checker microprocessor using an entire combination of the scan chain circuits. Thus, the electronic control unit of low-cost configuration is capable of performing a scan test by making use of part of the scan chain circuits designed for the component inspection.

Description

BACKGROUND OF THE INVENTION[0001]1. Technical Field[0002]The present invention relates to an electronic control unit that has an integrated circuit element and is mounted in, for example, a vehicle, and relates to a component test unit that performs in the product shipment stage a rationalized anomaly check associating mutually an anomaly check for the electronic control unit in actual operation with a component anomaly check for the integrated circuit element built in the electronic control unit.[0003]2. Description of the Related Art[0004]In an electronic control unit mounted in, for example, a vehicle that includes an input interface circuit connected to input sensors; an output interface circuit connected to electric loads; and at least one integrated circuit element connected with the input interface circuit and the output interface circuit, the electronic control unit performs during operation a check on connection states of wirings to the input sensors and the electric loads ...

AI Technical Summary

Benefits of technology

The present invention provides an electronic control unit with a built-in self-test circuit that includes a self-test control block, scan chain circuits, and mask circuitry. The integrated circuit element can select between two combinations of scan chain circuits for self-testing, and an external test can be performed on the built-in self-test control block during shipment inspection without needing to generate a diagnostic pulse-train signal. This improves the reliability of the integrated circuit element and ensures accurate and reliable self-testing.

Problems solved by technology

However, no detail checks are made individually on the various combination circuits, with the microprocessor and the monitoring and control circuit section being halted.

In particular, it is difficult to perform quickly the detail checks within a limited permissible time at start of operation; therefore such detail checks have been unachieved.

Therefore, a detail check for various combination circuits cannot be performed by making use of these scan pass circuits (scan chain circuits), with the integrated circuit element assembled into the actual electronic control unit.

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